1. Field of the Invention
The present invention relates to a data reading apparatus wherein the relative position between a TV camera and a tag is maintained constant and a deflecting coil of the TV camera is mechanically rotated or a signal which is equivalent to the mechanical rotation of a deflecting coil is applied to the deflecting coil whereby the tag having bar codes in discretional directions is read by the TV camera.
2. Description of the Prior Art
In apparatus for reading out the data of tags written by bar codes or in a special font, wherein the tags are attached to commodities or the like, the plane of the target of the TV camera is disposed substantially parallel to a plane of the tag at a constant distance to the plane of the tag. However, the direction is dependent upon the position of the commodity. In order to read out the data of bar codes having non-concentric circles which are written on tags, it is necessary to arrange the direction so as to scan all the data by at least one scanning line.
In order to arrange this, the following methods can be considered, though they are disadvantageous.
1. The direction of a camera is varied by rotation of the camera. An image on the target of the TV camera is rotated. Accordingly, the after-image phenomenon of the video tube of the TV camera prevents high speed rotation whereby high speed read-out is prevented.
2. A direction of an image on a target of the TV camera is varied by rotation of a prism. Here, high speed read-out is prevented because of a similar reason.